I've have had my 2007 e90 335i for about a month now and I have noticed that when I plug my Ipod in the auxiliary jack that sound quality is terrible. The speakers are completely fine if I play the radio or a cd. If I fool around with the aux cable at the input the front speakers will go in and out also. Is this a normal issue with the 335i and will the dealer acknowledge this? Tomorrow I will try another aux cable and ipod to see if that is the problem.

I had this problem before too. It was a bad cable, because I was using like a cheapo $2 from Radio Shack. Bought a 2 foot Monster Cable and all was good. Now I just burn MP3 CDs with 150 songs. They last a while and sound better.

hey you dont need to have a aux volume..... i had the same problem... it isnt the cable either... just turn the volume down on the ipod to about 50% and try it again, if your ipod is cranked all the way up you will have terrible sound... worked for me... should work fine.. if it doesnt it is prolly the cable...

Whenever possible, DO NOT use the headphone out of the iPod. It has to do with a mismatch in out- and input impedances and voltages. The headphone output is optimized for driving HEADPHONES only. The line output is optimized for aux inputs and it bypasses the iPod's volume and EQ settings to give a flat, strong signal.

hey you dont need to have a aux volume..... i had the same problem... it isnt the cable either... just turn the volume down on the ipod to about 50% and try it again, if your ipod is cranked all the way up you will have terrible sound... worked for me... should work fine.. if it doesnt it is prolly the cable...

Cheers.

I will try that once I get my car and ipod back from the dealer. I don't think my volume is up very far, probably about 70-80%, but maybe if I crank it down a bunch it'll go away.

You guys made my day! I have been so disappointed with the audio quality out of my iPad using the aux channel, almost to the point I considered selling the car and get one with an USB port. The aux volume took care of that!

Eh, kaigoss, you're technically correct about the impedance matching, but headphone outputs are very explicitly designed to be happy with a very wide range of load impedances. The BIGGEST problem is that you NEVER crank any volume to 100%. You probably don't need to sit the iPod at 50%, but whenever an audio system is designed, it usually is designed with a 10% or so overdrive in mind. The idea is that some songs hit the player with poor normalization. The recording happens to be quiet. And in that case, you can amplify by a larger factor and still remain within the drive characteristics of your system. HOWEVER, for normal volume recordings, by using that extra buffer, you're actually clipping the peaks of the output signal off totally and introducing distortion. It's true of both the iPod and radio - crank either to max and drop the other so it's comfortable, and you'll still hear distortion for most songs.

Whenever possible, DO NOT use the headphone out of the iPod. It has to do with a mismatch in out- and input impedances and voltages. The headphone output is optimized for driving HEADPHONES only. The line output is optimized for aux inputs and it bypasses the iPod's volume and EQ settings to give a flat, strong signal.

I don't believe it will bypass eq, based on experience. I do however recommend use of the dock connector.